Stockholm wins Mayors Challenge 2014

Stockholm was announced as five winners in Mayors Challenge in Paris today– an ideas competition for European cities focusing on urban challenges. Stockholm's competing area was the challenge of turning garden waste into biochar.

The competition is open to European cities with more than 100 000 citizens and has received 155 applications. The aim of the competing projects should be to solve essential challenges for citizens while at the same time improving the cities long term. The winning ideas should also be unique, but at the same time adaptable to other cities around the world.

The Stockholm project ”Biochar – for a better city ecosystem” aims at producing biochar from garden waste. Biochar is organic carbon that can be used as soil conditioner to increase plant and tree growth in the city. Increased green areas with healthy foliage in turn helps to create a greener and healthier city environment. In addition, when mixed with soil biochar can help combat climate change by sequestering carbon, thus adding yet another positive environmental factor to this project. Producing biochar could be a way of taking care of garden waste in a more resource efficient way, compared to today’s method of turning it to woodchips.

Behind the challenge are Bloomberg Philanthropies together with New York’s former Mayor Michael Bloomberg in cooperation with the organisation EUROCITIES.

The over-all winner receives five million Euros, and the four second-best cities receive one million Euros each to help develop their ideas.

Meet the winners.